Christian Science is overwhelmingly White, at least in the USA and Europe. There is an odd phenomenon that Christian Science, though likely in decline, is growing fastest in Africa. This is not likely to do with intellectual conviction though, it is more likely that in Africa there is less access to medicine so people rely on faith healing, and Christian Science is kind of like that. But in the West where there is medicine, Blacks don't convert to Christian Science. Why can this be?
Christian Science is basically almost not Christianity and is actually closer to Hinduism. Basically, you deny matter exists and if you try hard enough then your mind can control matter and you will be able to heal yourself. I think there is some kind of intense psychological state you need to enter using proper praying techniques and affirmations in order to experience healing according to Christian Science. This is kind of more like Hinduism than Christianity.
Christianity is anti-intellectual, but maybe because Christian Science veers from traditional Christianity it is a little more open. Don't get me wrong, there is plenty of anti-intellectualism going on in Christian Science, they don't let their children learn anything about medicine or biology, but even then it is an intellectual conviction because the idea is that if you believe in biology it will take over your mind and you will live in the material world and be subject to disease. If you don't even understand biology then supposedly it has less of an effect on you and your mind can do all the thinking free of the constraints of science and supposedly keep you free of disease.
The point is that Christian Science is kind of a thought movement whereas traditional Christianity is more of a faith movement, there is a difference between trying to transmute matter by denying material existence and simply saying Jesus is king and thinking that simply believing in him will get you to heaven. Don't get me wrong, denying matter is not intellectual, however, the idea of organizing your being so you may conquer reality is more strenuous of a task than simply having faith, Christian Science is a lot more mental work.
Christian Scientists tend to be wealthier and more educated than the average person, and this is likely because the cult attracts the intelligentsia... in its heyday, it was popular in Hollywood and among top-name people. Some fallacies are picked up by brighter minds more than the average population, especially if they are complicated fallacies that can almost seem true at times. Complicated minds don't fall for simple traps like traditional Christianity. The point is that the darker races have simpler minds and so they only respond to simple mind tricks, Christian Science is too complex for them to grasp and so they can't fall for the trick because they can't understand it.